The Core consists of three parts: a Clinical Core, an Animal Core, and a Histology Core. The Clinical Core provides state-of-the-art cable EEG telemetry with scalp and sphenoidal or intracerebral electrodes and video monitoring;complete surgical facilities for surgical resection and stereotactic placement of depth electrodes when necessary;ancillary diagnostic testing, including CT, MRI, PET, MEG, fMRI, MRS, digital subtraction magnetic resonance angiography, specialized neurocognitive testing, intracarotid amobarbital procedures, quantitative EEG analysis;and a team of neurosurgeons, neurologists, clinical neurophysiologists, a psychiatrist, a neuropsychologist, a neuroradiologist, clinical nurse-specialists, and telemetry technologists, all specialized in epilepsy, as well as personnel for technical and administrative support. Diagnostic and surgical procedures are standardized for best patient care, which also facilitates application of clinical data to basic research projects. The Animal Core is responsible for preparation of the pilocarpine rat and mouse models used by all investigators, with video-EEG facilities and personnel to monitor animals on a continuous basis, behaviorally to detect seizure occurrence, and electrophysiologically, in order to characterize the development of interictal and ictal epileptiform events when this is necessary. The Histology Core is responsible for carrying out routine cell counts, Timm's stain, immunocytochemistry, neurobiotin recovery and image analysis of human, rat, and mouse tissue used for experiments in the three subprojects. The specific aims of the Core are to: i) assure that all patients entered into the CNP protocols receive the best possible clinical care, and that research projects do not create additional risk, discomfort, or financial burden; ii) ensure that all clinical and animal data necessary for carrying out CNP research projects are made available to CNP investigators;iii) improve presurgical evaluation and surgical treatment of human temporal lobe epilepsy, and the cost-effective use of animal models to expand research on this disorder;and iv) coordinate both clinical and animal research being carried out collaboratively among the three Subprojects.